the second nearest planet to the sun; it is peculiar in that its rotation is slow and retrograde (in the opposite sense of the Earth and all other planets except Uranus); it is visible from Earth as an early `morning star' or an `evening star'

(cosmology) a universe that is spatially closed and in which there is sufficient matter to halt the expansion that began with the big bang; the visible matter is only 10 percent of the matter required for closure but there may be large amounts of dark matter

(astronomy) any of the nine large celestial bodies in the solar system that revolve around the sun and shine by reflected light; Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto in order of their proximity to the sun; viewed from the constellation Hercules, all the planets rotate around the sun in a counterclockwise direction